Hip joint device and method

ABSTRACT

A medical device for treating hip joint osteoarthritis in a human patient by providing at least one artificial hip joint surface is provided. The hip joint having a ball shaped caput femur as the proximal part of the femoral bone with a convex hip joint surface towards the center of the hip joint and a bowl shaped etabulum as part of the pelvic bone with a concave hip joint surface towards the center of the hip joint. The medical device comprises the artificial hip joint surface comprising at least one of; an artificial caput femur or an artificial caput femur surface comprising, a convex form towards the center of the hip joint, and an artificial acetabulum or an artificial acetabulum surface comprising, a concave form towards the center of the hip joint. The artificial convex caput femur or the artificial convex caput femur surface is adapted to be fixated to the pelvic bone of the human patient and the artificial concave acetabulum or artificial concave acetabulum surface is adapted to be fixated to the femoral bone of the human patient.

This application is the U.S. national phase of International ApplicationNo. PCT/SE2010/050807, filed 12 Jul. 2010, which designated the U.S. andclaims the benefit of U.S. Provisional Nos.: 61/229,738 filed 30 Jul.2009, 61/229,739 filed 30 Jul. 2009; 61/229,743 filed 30 Jul. 2009;61/229,745 filed 30 Jul. 2009; 61/229,746 filed 30 Jul. 2009; 61/229,747filed 30 Jul. 2009; 61/229,748 filed 30 Jul. 2009; 61/229,751 filed 30Jul. 2009; 61/229,752 filed 30 Jul. 2009; 61/229,755, filed 30 Jul.2009; 61/229,761 filed 30 Jul. 2009; 61/229,767 filed 30 Jul. 2009;61/229,778 filed 30 Jul. 2009; 61/229,786 filed 30 Jul. 2009; 61/229,789filed 30 Jul. 2009; 61/229,796 filed 30 Jul. 2009; and 61/229,735 filed30 Jul. 2009; and which claims priority to Swedish Application Nos.:0900981-2 filed 10 Jul. 2009; 0900957-2 filed 10 Jul. 2009; 0900959-8filed 10 Jul. 2009; 0900960-6 filed 10 Jul. 2009; 0900962-2 filed 10Jul. 2009; 0900963-0 filed 10 Jul. 2009; 0900965-5 filed 10 Jul. 2009;0900966-3 filed 10 Jul. 2009; 0900968-9 filed 10 Jul. 2009; 0900969-7filed 10 Jul. 2009; 0900970-5 filed 10 Jul. 2009; 0900972-1 filed 10Jul. 2009; 0900973-9 filed 10 Jul. 2009; 0900974-7 filed 10 Jul. 2009;0900976-2 filed 10 Jul. 2009; 0900978-8 filed 10 Jul. 2009; and0900958-0 filed 10 Jul. 2009, the entire contents of each of which arehereby incorporated by reference.

FIELD OF INVENTION

The present invention relates generally to a medical device forimplantation in a hip joint, and a method of providing said medicaldevice.

BACKGROUND

Hip joint Osteoarthritis is a syndrome in which low-grade inflammationresults in pain in the hip joints, caused by abnormal wearing of theCartilage that acts as a cushion inside if the hip joint. This abnormalwearing of the cartilage also results in a decrease of the jointslubricating fluid called Synovial fluid. Hip joint Osteoarthritis isestimated to affect 80% of all people over 65 years of age, in more orless serious forms.

The present treatment for hip osteoarthritis comprises NSAID drugs,local injections of Hyaluronic acid or Glucocorticoid to helplubricating the hip joint, and replacing parts of the hip joint with aprosthesis through hip joint surgery.

The replacing of parts of the hip joint is one of the most commonsurgeries to date performed at hundreds of thousands of patients in theworld every year. The most common method comprises placing a metalprosthesis in Femur and a plastic bowl in Acetabulum. This operation isusually done through a lateral incision in the hip and upper thigh andthrough, Fascia Lata and the lateral muscles of the thigh. To get accessto the hip joint, the supporting hip joint capsule attached to Femur andIlium of Pelvis needs to be penetrated, making it difficult to get afully functional joint after the surgery. Femur is then cut at the neckwith a bone saw and the prosthesis is placed in femur either with bonecement or without. Acetabulum is slightly enlarged using an Acetabularreamer, and the plastic bowl is positioned using screws or bone cement.

The surgery typically requires one week of hospitalization due to theincreased risk of infection. The recovery process is on average about 6weeks, but even after this period the patient should not perform anyphysical activates that places large strain on the joint.

SUMMARY

A medical device for treating hip joint osteoarthritis in a humanpatient by providing at least one artificial hip joint surface isprovided. The hip joint having a ball shaped caput femur as the proximalpart of the femoral bone with a convex hip joint surface towards thecentre of the hip joint and a bowl shaped acetabulum as part of thepelvic bone with a concave hip joint surface towards the centre of thehip joint. The medical device comprising the artificial hip jointsurface comprises at least one of; an artificial caput femur or anartificial caput femur surface comprising, a convex form towards thecentre of the hip joint, and an artificial acetabulum or an artificialacetabulum surface comprising, a concave form towards the centre of thehip joint. The artificial convex caput femur or the artificial convexcaput femur surface is adapted to be fixated to the pelvic bone of thehuman patient, and the artificial concave acetabulum or artificialconcave acetabulum surface is adapted to be fixated to the femoral boneof the human patient.

Alternatively a medical device for treating hip joint osteoarthritis byproviding at least one joint surface is provided. The hip joint has aball shaped caput femur as the proximal part of the femoral bone with aconvex hip joint surface and a bowl shaped acetabulum as part of thepelvic bone with a concave hip joint surface.

The medical device could comprise an artificial convex hip joint surfaceadapted to replace the convex hip joint surface. The artificial convexhip joint surface could be adapted to be fixated to the pelvic bone ofthe human patient.

According to one embodiment, the medical device comprises an artificialconvex hip joint surface adapted to be inserted through a hole in thepelvic bone of the human patient.

According to one embodiment, the medical device comprises an artificialconvex hip joint surface adapted to be inserted through a hole in thehip joint capsule of the human patient.

According to one embodiment, the medical device comprises an artificialconvex hip joint surface adapted to be inserted through a hole in thefemoral bone of the human patient.

The medical device could be adapted to be placed in an artificialreplacement of the concave acetabulum hip joint surface. The artificialreplacement could be adapted to be fixated to the caput femur, thecollum femur or the femoral bone.

According to one embodiment the artificial convex hip joint surface inthe medical device comprises at least two artificial hip joint surfaceparts adapted to be placed in connection with each other after theinsertion in the human patient. The at least two artificial hip jointsurface parts could be adapted to be inserted through a hole in thepelvic bone from the opposite side from acetabulum of the human patient,said hole having a diameter less than the largest diameter of saidmedical device. It is also conceivable that the at least two artificialhip joint surface parts are adapted to be inserted through a hole in thefemoral bone or the hip joint capsule of the human patient. The holehaving a diameter smaller than the largest diameter of the medicaldevice.

According to any of the embodiments above, at least one of said at leasttwo artificial hip joint surface parts could be adapted to serve as basepart to which at least one additional artificial caput femur surfacepart can be connected.

The connection of said at least two artificial hip joint surface partscould be performed using at least one of: at least one screw, at leastone pin, at least one portion of at least one of the parts adapted to beintroduced into the other part, the parts being adapted to be slidinginto the other part, form fitting, welding, adhesive, pin, wire, a ballmounted into a bowl being portions of said parts, a male portion of onepart mounted into a female portion of the other part, a key introducedinto a lock being portions of said parts, band, or other mechanicalconnecting members. It is also conceivable that the at least twoartificial hip joint surface parts are adapted to mechanically connectto each other using self locking members, in which case the self lockingmembers could be assisted by adhesive or bone cement.

According to one embodiment, the medical device comprises at least oneelastic member. The at least one elastic member could be adapted forchanging the largest diameter or largest cross-sectional distance of themedical device for insertion through a hole having a diameter smallerthan said largest diameter or cross-sectional distance of said medicaldevice.

Fixation

To fixate the medical device it is conceivable that the medical devicecomprises a fixation support to anchor the artificial convex hip jointsurface. The fixation support is adapted to anchor the artificial convexhip joint surface to the pelvic bone, to support at least part of theload applied to the hip joint in normal use.

According to one embodiment the fixation support comprises adisplaceable part or section. The displaceable part or section could beadapted to carry the load applied to the hip joint in normal use.

According to one embodiment the medical device could be adapted to befixated to the pelvic bone using at least one of: at least one screw, atleast one pin, at least one portion of at least one of the parts adaptedto be introduced into the other part, the parts being adapted to besliding into the other part, form fitting, welding, adhesive, pin, wire,a ball mounted into a bowl being portions of said parts, a male portionof one part mounted into a female portion of the other part, a keyintroduced into a lock being portions of said parts, band, or othermechanical connecting members.

According to one embodiment the medical device could be fixated to thepelvic bone without penetration of the cortex of the pelvic bone. It isalso conceivable that the medical device is adapted to be fixated to thepelvic bone by means of said elastic member exerting a clamping force onthe pelvic bone.

Material

The medical device according to any of the embodiments above couldcomprise at least one of the materials: polyethylene based material,PTFE, Corian, titanium, stainless steel, wolfram, other metal material,a combination of metal material, carbon fiber, boron, a combination ofmetal and plastic materials, a combination of metal and carbon basedmaterial, a combination of carbon and plastic based material,multi-material, wherein one material comprise a flexible material,multi-material, wherein one material comprise an elastic material,multi-material, wherein one material comprising more parts than theother at least one material, PE, and an acrylic polymer. It is alsoconceivable that the medical device comprises a self lubricatingmaterial. In cases where the medical device does not comprise a selflubricating material or if the self lubricating material is notsufficient it is conceivable that the medical device is adapted to belubricated after insertion in the hip joint.

According to one embodiment the medical device could be adapted to belubricated after insertion in the hip joint. It is furthermoreconceivable that the medical device comprises a self lubricatingmaterial such as PTFE.

The Acetabulum Surface

The present invention further relates to a medical device for treatinghip joint osteoarthritis in a human patient by providing at least oneartificial hip joint surface. The hip joint has a ball shaped caputfemur as the proximal part of the femoral bone with a convex hip jointsurface and a bowl shaped acetabulum as part of the pelvic bone with aconcave hip joint surface.

The medical device comprises an artificial concave hip joint surface,adapted to be fixated to at least one of: caput femur, collum femur oranother part of the femoral bone

According to one embodiment, the medical device comprises an artificialconcave hip joint surface adapted to be inserted through a hole in thepelvic bone of the human patient.

According to one embodiment, the medical device comprises an artificialconcave hip joint surface adapted to be inserted through a hole in thehip joint capsule of the human patient.

According to one embodiment, the medical device comprises an artificialconcave hip joint surface adapted to be inserted through a hole in thefemoral bone of the human patient.

According to one embodiment the artificial concave hip joint surface isfurther adapted to be placed in connection with an artificialreplacement of the convex hip joint surface. The artificial replacementcould be adapted to be fixated to the pelvic bone.

According to one embodiment the artificial concave hip joint surfacecomprises at least two artificial hip joint surface parts adapted to beplaced in connection with each other after the insertion in the humanpatient.

The at least two artificial hip joint surface parts could be adapted tobe inserted through a hole in the pelvic bone from the opposite sidefrom acetabulum of the human patient, said hole having a diameter lessthan the largest diameter of said medical device. It is also conceivablethat the at least two artificial hip joint surface parts are adapted tobe inserted through a hole in the femoral bone or the hip joint capsuleof the human patient. The hole having a diameter less than the largestdiameter of said medical device.

According to any of the embodiments above, at least one of said at leastIwo artificial hip joint surface parts could be adapted to serve as basepart to which at least one additional artificial caput femur surfacepart can be connected.

The connection of said at least two artificial hip joint surface partscould be performed using at least one of: at least one screw, at leastone pin, at least one portion of at least one of the parts adapted to beintroduced into the other part, the parts being adapted to be slidinginto the other part, form fitting, welding, adhesive, pin, wire, a ballmounted into a bowl being portions of said parts, a male portion of onepart mounted into a female portion of the other part, a key introducedinto a lock being portions of said parts, band, or other mechanicalconnecting members. It is also conceivable that the at least twoartificial hip joint surface parts are adapted to mechanically connectto each other using self locking members, in which case the self lockingmembers could be assisted by adhesive or bone cement.

According to one embodiment of the present invention the medical devicecomprises at least one elastic member. The at least one elastic membercould be adapted for changing the largest diameter or largestcross-sectional distance of the medical device for insertion through ahole having a diameter smaller than said largest diameter orcross-sectional distance of said medical device.

Fixation

To fixate the medical device according to the present invention it isconceivable that the medical device comprises a fixation support toanchor said artificial concave hip joint surface. The fixation supportis adapted to anchor said artificial concave hip joint surface to thecaput femur, the collum femur or another part of the femoral bone of thehuman patient, to at least partly support the load applied to the hipjoint in normal use.

The medical device according to one embodiment, wherein said fixationsupport comprises a displaceable part or section, and wherein saiddisplaceable part or section is adapted to carry the load applied to thehip joint in normal use.

According to one embodiment the medical device could be adapted to befixated to caput femur, the collum femur or the femoral bone using atleast one of: at least one screw, at least one pin, at least one portionof at least one of the parts adapted to be introduced into the otherpart, the parts being adapted to be sliding into the other part, formfitting, welding, adhesive, pin, wire, a ball mounted into a bowl beingportions of said parts, a male portion of one part mounted into a femaleportion of the other part, a key introduced into a lock being portionsof said parts, band, or other mechanical connecting members. It is alsoconceivable that the fixation is done using self locking members, inwhich case the self locking members could be assisted by adhesive orbone cement.

According to one embodiment the medical device could be fixated to thecaput femur, the collum femur or the femoral bone without penetration ofthe cortex of the pelvic bone. It is also conceivable that the medicaldevice is adapted to be fixated to the caput femur, the collum femur orthe femoral bone by means of said elastic member exerting a clampingforce on the caput femur, collum femur or femoral bone.

Material

The medical device according to any of the embodiments could comprise atleast one of the materials: polyethylene based material, PTFE, Corian,titanium, stainless steel, wolfram, other metal material, a combinationof metal material, carbon fiber, boron, a combination of metal andplastic materials, a combination of metal and carbon based material, acombination of carbon and plastic based material, multi-material,wherein one material comprise a flexible material, multi-material,wherein one material comprise an elastic material, multi-material,wherein one material comprising more parts than the other at least onematerial, PE, and an acrylic polymer. It is also conceivable that themedical device comprises a self lubricating material. In cases where themedical device do not comprise a self lubricating material or if theself lubricating material is not sufficient it is conceivable that themedical device is adapted to be lubricated after insertion in the hipjoint.

The System

The present invention further relates to a medical device system fortreating hip joint osteoarthritis in a human patient by providing atleast two hip joint surfaces. The system comprising the artificialconvex hip joint surface according to any of the embodiments above andthe artificial concave hip joint surface according to any of theembodiments above.

The artificial convex hip joint surface in the medical device systemcould be adapted to be placed, at least partly, inside of saidartificial concave hip joint surface.

According to one embodiment the artificial convex hip joint surfacecomprises a largest diameter and said artificial concave hip jointsurface could be adapted to travel beyond the largest diameter of theartificial convex hip joint surface.

According to one embodiment the medical device system has a ball shapedcaput femur as the proximal part of the femoral bone with a convex hipjoint surface, and a bowl shaped acetabulum as part of the pelvic bonewith a concave hip joint surface. The artificial convex hip jointsurface could be adapted to be placed, at least partly, inside of thecaput femur.

According to one embodiment the medical device could be adapted to belubricated after insertion in the hip joint. Said lubrication ispreferably done with a biocompatible lubricator such as hyaluronic acid.It is furthermore conceivable that the medical device comprises a selflubricating material such as PTFE.

Centering Device

According to one embodiment the medical device comprising an artificialacetabulum or an artificial acetabulum surface, wherein said elongatedmember is adapted to centre and hold said artificial acetabulum or anartificial acetabulum surface during fixation in the hip joint.

According to one embodiment the medical device comprising an artificialcaput femur or an artificial caput femur surface, wherein said elongatedmember is adapted to centre and hold said artificial caput femur or anartificial caput femur during fixation in the hip joint.

According to one embodiment said elongated member is adapted to centreand hold both said artificial caput femur or an artificial caput femurand said artificial acetabulum or an artificial acetabulum surfaceduring fixation in the hip joint.

According to one further embodiment of the medical device, theartificial caput femur surface comprises a convex form towards thecentre of the hip joint and the artificial acetabulum surface comprisesa concave form towards the centre of the hip joint. The artificial caputfemur surface and the artificial acetabulum surface is constructed to beplaced in the hip joint in a opposite position towards each other, thus;the artificial convex caput femur surface is adapted to be fixated tothe pelvic bone of the human patient, and the artificial concaveacetabulum surface is adapted to be fixated to the femoral bone of thehuman patient.

According to one embodiment the artificial acetabulum or artificialacetabulum surface is adapted to be centered and held by said elongatedmember, during fixation in the hip joint.

According to one embodiment the artificial caput femur or an artificialcaput femur surface is adapted to be centered and held by the elongatedmember, during fixation in the hip joint.

The Method

A further aspect of the present invention is a method of treating hipjoint osteoarthritis in a human patient by providing at least one hipjoint surface. The method comprises the steps of: fixating theartificial convex hip joint surface, according to any of the embodimentsabove, to the pelvic bone, and fixating the artificial concave hip jointsurface according to any of the embodiments above to at least one of;the caput femur, the collum femur or the femoral bone of the humanpatient.

The method could further comprise, the steps of: cutting the skin of thehuman patient, dissecting an area of the pelvic bone on the oppositeside from the acetabulum, creating a hole in said dissected area, saidhole passing through the pelvic bone and into the hip joint of the humanpatient, inserting said artificial hip joint surfaces into the hip jointthrough said hole. After the steps of fixating the artificial convex hipjoint surface, according to any of the embodiments above, to the pelvicbone, and fixating the artificial concave hip joint surface according toany of the embodiments above to at least one of; the caput femur, thecollum femur or the femoral bone of the human patient, the methodfurther comprises the steps of: Closing the hole in the pelvic boneusing bone material or a prosthetic part and closing, preferable inlayers, the hip area of the human patient using sutures or staples.

According to a second embodiment the method is a method of treating hipjoint osteoarthritis by providing artificial hip joint surfacesaccording to any of the embodiments above. The hip joint comprises aball shaped caput femur as the proximal part of the femoral bone with aconvex hip joint surface and a bowl shaped acetabulum as part of thepelvic bone with a concave hip joint surface, the method comprises thesteps of: cutting the skin of the human patient, dissecting an area ofthe hip joint, creating a hole in the hip joint capsule, inserting saidartificial hip joint surfaces into the hip joint through said hole inthe hip joint capsule, fixating the artificial convex hip joint surfacedevice to the pelvic bone, fixating the concave artificial hip jointsurface to at least one of; the caput femur, the collum femur or thefemoral bone, and closing, preferable in layers, the hip area of thehuman patient using sutures or staples or adhesive.

According to a third embodiment the method of treating hip jointosteoarthritis by providing artificial hip joint surfaces according toany of the embodiments above is a arthroscopic method. The hip jointcomprises a ball shaped caput femur as the proximal part of the femoralbone with a convex hip joint surface and a bowl shaped acetabulum aspart of the pelvic bone with a concave hip joint surface, the methodcomprises the steps of: inserting a needle or a tube like instrumentinto the patient's body, using the needle or tube like instrument tofill a part of the patient's body with gas and thereby expanding acavity within said body, placing at least two arthroscopic trocars insaid cavity, inserting a camera through one of the arthroscopic trocarsinto said cavity, inserting at least one dissecting tool through one ofsaid at least two arthroscopic trocars, dissecting an area of the pelvicbone on the opposite side from the acetabulum, creating a hole in saiddissected area, said hole passing through the pelvic bone and into thehip joint of the human patient, and providing said artificial hip jointsurfaces to the hip joint, through said hole in the pelvic bone of thehuman patient.

According to a third embodiment the method of treating hip jointosteoarthritis by providing artificial hip joint surfaces according toany of the embodiments above is a second arthroscopic method. The hipjoint comprises a ball shaped caput femur as the proximal part of thefemoral bone with a convex hip joint surface and a bowl shapedacetabulum as part of the pelvic bone with a concave hip joint surface,the method comprises the steps of: inserting a needle or a tube likeinstrument into the patient's body, using the needle or tube likeinstrument to fill a part of the patient's body with gas and therebyexpanding a cavity within said body, placing at least two arthroscopictrocars in said cavity, inserting a camera through one of thearthroscopic trocars into said cavity, inserting at least one dissectingtool through one of said at least two arthroscopic trocars, dissectingan area of the hip joint, creating a hole in the hip joint capsule,inserting said artificial hip joint surfaces into the hip joint throughsaid hole in the hip joint capsule, fixating the artificial convex hipjoint surface device to the pelvic bone, fixating the concave artificialhip joint surface to at least one of; the caput femur, the collum femuror the femoral bone, and closing, preferable in layers, the hip area ofthe human patient using sutures or staples or adhesive.

According to one embodiment the method of manipulation comprises thesteps of; fixating an artificial acetabulum surface to the pelvic bone,wherein said elongated member; centers the artificial acetabulumsurface, when the artificial acetabulum surface is fixated in the hipjoint.

According to one embodiment the method of manipulation comprises thestep of; fixating an artificial caput femur surface to the femoral bone,wherein said elongated member; centers said artificial caput femursurface, when said artificial caput femur surface is fixated in the hipjoint.

According to one embodiment, a method of centering an artificial hipjoint surface in a hip joint of a human patient is provided. The hipjoint comprising a collum femur, being the proximal part of the femoralbone, a caput femur, being the upper extremity of the femoral bone, andan acetabulum, being a bowl shaped part of the pelvic bone, the methodcomprising the steps of: penetrating the skin of a lateral section ofthe thigh, creating a hole in the collum femur, along a length axisthereof, reaching an area of the hip joint, placing an elongated memberin said hole, wherein said elongated member reaches centrally in saidarea of the hip joint, and centering said artificial hip joint surfaceonto said elongated member, wherein the artificial hip joint surfacecomprises a centre hole for guiding the elongated member, and placingthe said artificial hip joint surface in a functional position in thehip joint.

The artificial hip joint surface, according to any of the embodimentsabove may comprise an artificial convex caput femur or an artificialconvex caput femur surface or an artificial concave acetabulum or anartificial concave acetabulum surface.

According to one embodiment the step of fixating said artificialacetabulum surface further comprises the step of placing a lockingmember in connection with the artificial acetabulum surface, such thatsaid artificial acetabulum surface remains clasped to said surgicallycut femoral bone.

According to one embodiment the step of placing a locking membercomprises the step of placing a locking member encircling the artificialacetabulum surface and the surgically cut caput femur.

The collum femur has a longitudinal extension, and a fixating member atleast partly be positioned on and stabilized by the cortical bone ofsaid stabilizing part of the collum femur from two different aspects ofthe collum femur, the method could comprise the steps of; positioningand stabilizing said fixating member from the inside of said stabilizingpart of the collum femur, substantially perpendicular to thelongitudinal extension thereof, and from the acetabulum sidesubstantially in line with the longitudinal extension of the collumfemur.

The collum femur has a longitudinal extension and a fixating member atleast partly be positioned on, and stabilized by the cortical bone ofsaid stabilizing part of the collum femur from three different aspectsof the collum femur. The method could comprise the steps of; positioningand stabilizing said fixating member from the inside of said stabilizingpart of the collum femur substantially perpendicular to the longitudinalextension thereof, from the acetabulum side substantially in line withthe longitudinal extension of the collum femur and from the outside ofthe collum femur substantially perpendicular to the longitudinalextension thereof.

Please note that any embodiment or part of embodiment as well as anymethod or part of method could be combined in any way. All examplesherein should be seen as part of the general description and thereforepossible to combine in any way in general terms.

BRIEF DESCRIPTION OF DRAWINGS

The invention is now described, by way of example, with reference to theaccompanying drawings, in which:

FIG. 1 a shows the hip joint in section,

FIG. 1 b shows the collum femur in section,

FIG. 2 shows the exposing of the caput femur through an incision in thethigh,

FIG. 3 shows the step of removing a proximal part of the caput femur,

FIG. 4 a shows the reaming of the collum and caput femur,

FIG. 4 b shows the injecting of an adhesive in the acetabulum

FIG. 5 shows the collum and caput femur when a medical device gas beenfixated,

FIG. 6 a shows the femoral bone when a medical device having a concavecontacting surface has been provided to the hemi-spherical cavity showsthe reaming of the acetabulum,

FIG. 6 b shows the femoral bone when a medical device having a concavecontacting surface has been provided to the hemi-spherical cavity,

FIG. 6 c shows an alternative embodiment, in which the medical devicehas been fixated to the surgically cut caput femur using screws,

FIG. 6 d shows yet another embodiment, in which the medical device isfixated to the femoral bone using fixating portions,

FIG. 6 e shows yet an alternative embodiment of the medical device inwhich the fixating portions are additionally fixated using screws,

FIG. 7 a shows the medical device in an embodiment in which the fixatingportions extends beyond the greatest circumference of the surgically cutcaput femur,

FIG. 7 b shows yet another embodiment where the medical device isadditionally fixated using a fixating band,

FIG. 7 c shows three different embodiment of medical devices comprisingfixating portions,

FIG. 7 d shows two embodiments in which the concave contacting surfaceonly comprises the part placed inside of the concave cavity,

FIG. 7 e shows two embodiments in which the artificial acetabulumsurface extends into a portion placed on the surface of a sectioncreated when the caput femur is surgically cut.

FIG. 7 f describes an embodiment in which the medical device is furtherfixated using an elongated member,

FIG. 8 shows the artificial acetabulum surface in further detail whenthe artificial acetabulum surface comprises a fixating portion,

FIG. 9 shows a section of the medical device,

FIG. 10 a shows the step of milling the periphery of the cortical boneof the caput femur after the caput femur has been surgically cut,

FIG. 10 b shows the milling of the inside of the cortical bone of thecaput femur after the caput femur has been surgically cut,

FIG. 11 shows an artificial convex caput femur surface adapted to beplaced in an artificial acetabulum surface according to any of theembodiments herein,

FIG. 12 shows the artificial convex caput femur surface when mounted inan artificial acetabulum surface,

FIG. 13 shows the artificial convex caput femur surface when mounted inan artificial acetabulum surface,

FIG. 14 shows the injection of an adhesive in the acetabulum in thepelvic bone using an injecting member,

FIG. 15 shows the placing of a medical device in the reamed acetabulumsurface of the pelvic bone,

FIG. 16 a shows the step of creating a hole in the pelvic bone from theacetabulum side of the pelvic bone,

FIG. 16 b shows the medical device according to an embodiment in whichthe medical device comprises a fixation element,

FIG. 16 c shows the expandable portion when the anvil member has pressedthe expandable elements in two directions,

FIG. 16 d shows the elongated member in the wholly expanded statefixating the artificial caput femur to the pelvic bone,

FIG. 16 e shows the medical device according to an embodiment in whichthe implantable medical device comprises an elongated element,

FIG. 16 f shows the movable locking portion,

FIG. 16 g shows the medical device when the movable member is placed inthe second state,

FIG. 16 h shows an embodiment in which the fixation element comprises afixation surface comprising two holes,

FIG. 16 i shows the artificial hip joint in section,

FIG. 17 a shows an assembled artificial hip joint with an artificialcaput femur surface,

FIG. 17 b shows an embodiment similar to the embodiment shown in FIG. 17a with the difference that the artificial acetabulum surface is fixatedusing an elongated member,

FIG. 17 c shows an embodiment similar to the embodiment shown in FIG. 17a with the difference that the artificial acetabulum surface is fixatedusing an elongated member,

FIG. 18 a shows an embodiment where the artificial acetabulum is fixatedto the femoral bone using fixating portions,

FIG. 18 b shows an embodiment similar to the embodiment described withreference to

FIG. 18 a with the difference that the locking member is fixated to thesurgically cut caput femur using screws,

FIG. 19 shows the hip joint in section when the medical device isassembled and in its functional position in the hip joint,

FIG. 20 shows a frontal view of a human patient when an incision forreaching an area of the hip joint through the pelvic bone in a surgicalmethod has been performed,

FIG. 21 shows a frontal view of a human patient when small incisions forreaching an area of the hip joint through the pelvic bone in aarthroscopic method has been performed,

FIG. 22 shows the human patient in section when a medical device forcreating a hole in the pelvic bone,

FIG. 23 shows the hip joint in section after the medical device forcreating a hole in the pelvic bone has created said hole,

FIG. 24 shows how the medical device adapted to create a hole isinserted into the hip joint and placed in contact with the caput femur,

FIG. 25 shows the hip joint in section when a second medical devicesurgically removes the most proximal portion of the caput femur,

FIG. 26 shows the second medical device when the drilling portion ispositioned inside of the femoral bone,

FIG. 27 shows a medical device comprising an artificial convex hip jointsurface,

FIG. 28 shows the hip joint in section when the artificial convex hipjoint surface is fixated in the medical device,

FIG. 29 shows the placing of a prosthetic part adapted to occupy thehole created in the pelvic bone,

FIG. 30 shows the hip joint in section when all the elements of themedical device has been fixated in the area of the hip joint or itssurroundings,

FIG. 31 shows the hip joint in section when the method of supplying themedical device is conducted according to another embodiment,

FIG. 32 shows the step of applying an adhesive to the concave surfacecreated by the reamer,

FIG. 33 shows the step of providing a medical device comprising anartificial concave hip joint surface,

FIG. 34 shows the hip joint in section when the artificial convex hipjoint surface is fixated in the medical device comprising a concave hipjoint surface,

FIG. 35 shows the placing of a prosthetic part adapted to occupy thehole created in the pelvic bone,

FIG. 36 shows the hip joint in section when all the elements of themedical device has been fixated in the area of the hip joint or itssurroundings.

FIG. 37 shows an embodiment of a locking member,

FIG. 38 shows the hip joint in section when a two state locking memberlocks the artificial caput femur in the artificial acetabulum,

FIG. 39 shows the hip joint in section according to the embodiment ofFIG. 38, but when the two state locking member is in its second state.

DETAILED DESCRIPTION

In the following a detailed description of preferred embodiments of thepresent invention will be given. In the drawing figures, like referencenumerals designate identical or corresponding elements throughout theseveral figures. It will be appreciated that these figures are forillustration only and are not in any way restricting the scope of theinvention. Thus, any references to direction, such as “up” or “down”,are only referring to the directions shown in the figures. Also, anydimensions etc. shown in the figures are for illustration purposes.

Functional hip movements are to be understood as movements of the hipthat at least partly correspond to the natural movements of the hip. Onsome occasions the natural movements of the hip joint might be somewhatlimited or altered after hip joint surgery, which makes the functionalhip movements of a hip joint with artificial surfaces somewhat differentthan the functional hip movements of a natural hip joint.

The functional position of an implantable medical device or prosthesisis the position in which the hip joint can perform functional hipmovements. The final position is to be understood as a functionalposition in which the medical device needs no further position change.

Arthroscopy is to be understood as key hole surgery performed in ajoint, since the arthroscopic procedure could be performed in theabdomen of the patient some of the steps of this arthroscopic procedureis more laparoscopic, however for the purpose of this invention the twoterms arthroscopy and laparoscopy is used synonymously and for thepurpose of this invention the main purpose of these methods are is thatthey are minimally invasive.

The medical device according to any of the embodiments could comprise atleast one material selected from a group consisting of:polytetrafluoroethylene (PTFE), perfluoroalkoxy (PFA) and fluorinatedethylene propylene (FEP). It is furthermore conceivable that thematerial comprises a metal alloy, such as cobalt-chromium-molybdenum ortitanium or stainless steel, or polyethylene, such as cross-linkedpolyethylene or gas sterilized polyethylene. The use of ceramic materialis also conceivable, in the contacting surfaces or the entire medicaldevice such as zirconium or zirconium dioxide ceramics or aluminaceramics. The part of the medical device in contact with human bone forfixation of the medical device to human bone could comprise a poorhousestructure which could be a porous micro or nano-structure adapted topromote the growth-in of human bone in the medical device for fixatingthe medical device. The porous structure could be achieved by applying ahydroxy-apatite (HA) coating, or a rough open-pored titanium coating,which could be produced by air plasma spraying, a combination comprisinga rough open-pored titanium coating and a HA top layer is alsoconceivable. The contacting parts could be made of a self lubricatedmaterial such as a waxy polymer, such as PTFE, PFA, FEP, PE and UHMWPE,or a powder metallurgy material which could be infused with a lubricant,which preferably is a biocompatible lubricant such as a Hyaluronic acidderivate. It is also conceivable that the material of contacting partsor surfaces of the medical device herein is adapted to be constantly orintermittently lubricated. According to some embodiments the parts orportions of the medical device could comprise a combination of metalmaterials and/or carbon fibers and/or boron, a combination of metal andplastic materials, a combination of metal and carbon based material, acombination of carbon and plastic based material, a combination offlexible and stiff materials, a combination of elastic and less elasticmaterials, Corian or acrylic polymers.

FIG. 1 a shows the hip joint of a human patient in section. The hipjoint comprises a caput femur 5 placed at the very top of collum femur 6which is the top part of the femoral bone 7. The caput femur is inconnection with the acetabulum 8, which is a bowl shaped part of thepelvic bone 9. Both the caput femur surface 10 and the acetabulumsurface 11 is covered with articular cartilage 13 which acts as acushion in the hip joint. In patients with hip joint osteoarthritis,this articular cartilage 13 is abnormally worn down due to a low gradeinflammation. The hip joint is surrounded by the hip joint capsule 12which provides support for the joint and hinders luxation. Afterconventional hip joint surgery, penetrating the hip joint capsule 12,the capsule 12 is dramatically weakened due to the limited healingpossibilities of its ligament tissue. By performing hip joint surgerywithout damaging the hip joint capsule 12 the patient can fully recoverand place equal amount of strain on an artificial joint as is possibleon a natural one.

FIG. 1 b shows a section A-A of the collum femur, as shown in FIG. 1.The section A-A shows the collum femur comprising cortical bone 601, theouter more sclerotic bone, and cancellous bone 602, the inner porousbone located in the bone marrow 603. Further, FIG. 1 b shows a sectionB-B of the caput femur, perpendicular to the length axis of the collum 6and caput 5 femur.

FIG. 2 shows a lateral view of a human patient when an incision in thethigh region has been made. The femoral bone 7 comprising the collumfemur 6 and the caput femur 5 has been dislocated from its usualposition in the hip joint, in connection with the acetabulum, which is apart of the pelvic bone 9, the caput femur 5 being a part of the hipjoint normally being covered by the hip joint capsule.

FIG. 3 shows the proximal part of the caput femur 5 being removed e.g.by means of a bone saw. A surface of a section 102 is thus createdperpendicularly to a length axis of the collum femur 6

FIG. 4 a shows the reaming of the collum femur 6 and caput femur 5 usinga reamer 40 connecting to an elongated member 21 by a connecting section101. The reamer 40 creating a hemi-spherical cavity, having a concavesurface 103, centrally placed in the caput 5 and collum femur 6.

FIG. 4 b shows the step of applying an adhesive 106 to the createdhemispherical cavity in the femoral bone using an injecting member 104having an injecting nozzle 105. In the embodiment shown in FIG. 4 b theinjecting member is inserted into an area of the hip joint through ahole 18 in the pelvic bone 9, however it is equally conceivable that theinjecting member is inserted through the hip joint capsule 12 or thefemoral bone 7.

FIG. 5 shows the femoral bone 7 when a medical device 109 having aconcave contacting surface has been provided to the hemi-sphericalcavity, centrally placed in the caput 5 and collum femur. An elasticlayer 109 b adapted to absorb shocks from the femoral bone has beenplaced between the surface 109 c adapted to be in contact with theartificial caput femur surface, and the femoral bone 7, 6. The elasticlayer 109 b could be an elastic polymer layer, such as a polyurethane orsilicone layer. Having a layer absorbing shocks in the hip joint reducesthe risk of fastening elements in contact with bone being affected bystrains such that the fastening elements are loosened from theirrespective fastening positions, it also increases the comfort for thepatient.

FIG. 6 a shows the femoral bone 7 when a medical device having a concavecontacting surface 110 has been provided to the hemi-spherical cavity,centrally placed in the caput 5 and collum femur. The medical device hasbeen fixated to the femoral bone 7 using screws 121 placed aligned withthe caput and collum femur center axis and entering the cortical bone ofthe caput femur.

FIG. 6 b shows the femoral bone 7 when a medical device having a concavecontacting surface 110 has been provided to the hemi-spherical cavity,centrally placed in the caput 5 and collum femur. The medical devicecomprises fixating portions 680 extending on the outside of the surfaceof a section 102 of the surgically cut caput femur, comprising corticalbone in the periphery thereof, thereby stabilizing the medical devicewith the artificial concave acetabulum surface 110 in the surgically cutcaput femur.

FIG. 6 c shows an alternative embodiment, in which the medical devicehas been fixated to the surgically cut caput femur using screws 121entering the cortical bone 601 of the caput femur.

FIG. 6 d shows yet another embodiment, in which the medical device isfixated to the femoral bone using fixating portions, in accordance withthe embodiment described with reference to FIG. 6 b, and an elongatedmember 681. The elongated member is according to this embodiment athreaded member 681 extending along the collum and caput femur centeraxis, in the cancellous bone 602 of the collum femur, and entering thecortical bone 601 of the femoral bone, on the inside thereof, in thearea of the greater trochanter. The threaded elongated member 681creates an axial force when pulled pressing the medical device towardsthe surface of a section 102 of the surgically cut caput femur, therebystabilizing and fixating the medical device in the concave cavitycreated in the caput femur.

FIG. 6 e shows yet an alternative embodiment of the medical device inwhich the fixating portions 680 are additionally fixated using screws121 placed from the outside of the surgically cut caput femur,perpendicularly to the collum and caput femur center axis.

FIG. 7 a shows the medical device in an embodiment in which the fixatingportions 680 extends beyond the greatest circumference of the surgicallycut caput femur and thereby clasps the medical device to the surgicallycut caput femur, fixating the medical device thereon. The concavecontacting surface 110 is also adapted to travel beyond the equator ofan artificial caput femur which is placed in the artificial acetabulumwhen mounted into a functioning artificial hip joint, and clasping theartificial caput femur when mounted therein.

FIG. 7 b shows yet another embodiment where the medical device isadditionally fixated using a fixating band 683 encircling the fixatingportions of the medical device and thereby further clasping the medicaldevice to the surgically cut caput femur.

FIG. 7 c shows three different embodiment of medical devices comprisingfixating portions 680 which are slightly tilted towards the collum andcaput femur center axis, thereby clasping a portion of the surgicallycut caput femur for fixating the medical device to the surgically cutcaput femur. The three different embodiments shown is first, withoutscrews 121, second, with screws entering the cortical bone, and third,with screws penetrating the cortical bone and entering the medicaldevice on the inside of the concave cavity, which enables the screws tosqueeze a portion of the cortical bone for tight fixation of the medicaldevice.

FIG. 7 d shows two embodiments in which the concave contacting surface110 only comprises the part placed inside of the concave cavity. Thefirst embodiment shows the acetabulum surface 110 fixated to the concavecavity using screws 121, whereas the second embodiment shows theartificial acetabulum surface fixated without screws, such as using anadhesive.

FIG. 7 e shows two embodiments in which the artificial acetabulumsurface extends into a portion placed on the surface of a sectioncreated when the caput femur is surgically cut. In the first embodimentthe medical device is fixated using screws entering the cortical bone,whereas in the second embodiment the artificial contacting surface isfixated without screws, such as using an adhesive.

FIG. 7 f describes an embodiment in which the medical device is furtherfixated using an elongated member 681, fixating portions 680, and screws121 placed between the fixating portions 680 and the inside of theartificial acetabulum contacting surface 110. The elongated member 681is according to this embodiment a threaded member 681 and the first fig.discloses the preparation of the cancellous bone 602 with a curing fluid685, such as bone cement, creating a sturdy base for the fixation of thethreaded member 681.

FIG. 8 shows the artificial acetabulum surface 110 in further detailwhen the artificial acetabulum surface comprises a fixating portion 680extending on the outside of the cortical bone 601. The fixating portion680 is further fixated using screws 121 placed from the outside, througha hole in the medical device, penetrating the cortical bone 601 of thesurgically cut caput femur and entering the medical device placed in theconcave cavity in the caput femur.

FIG. 9 shows a section of the medical device according to the embodimentalso described with reference to FIG. 7 a, in further detail. Themedical device according to the embodiment in FIG. 9 comprises fixatingportions 680 which reaches on the outside of the surgically cut caputfemur and clasps the cortical bone of the caput femur. The medicaldevice clasps the caput femur since a distance 687, between the collumand caput femur center axis CA and the fixating portion in shorter thana distance 686 between the collum and caput femur center axis CA and aportion of the fixating portion placed more proximally when the medicaldevice is implanted. On the inside of the artificial concave acetabulumsurface, the surface extends beyond the equator of the artificial caputfemur adapted to be placed therein. An extending portion 682 clasps theartificial caput femur placed in the artificial acetabulum surface 110since a distance 688, between the collum and caput femur center axis CAand the inside of the artificial acetabulum surface 110 is shorter thana distance 689 between the collum and caput femur center axis CA and apoint on the inside of the artificial acetabulum contacting surface 110being more distal when the medical device is implanted. In otherembodiments, the fixating portions 680 could be operable or adjustablefor further fixating the medical device to the cortical bone. Thefixating portions 680 could be operable for example by means of a screwfor tightening the fixating portions 680 to the cortical bone, whichcould squeeze the cortical bone between the fixating portions 680 andthe part of the medical device placed inside of the femoral bone.

FIG. 10 a shows the step of milling the periphery 690 of the corticalbone of the caput femur after the caput femur has been surgically cut,using a milling device 688 adapted therefor. The milling process createsa straighter edge which facilitates the fixation of a medical device onthe outside of the caput femur.

FIG. 10 b shows the milling of the inside of the cortical bone of thecaput femur after the caput femur has been surgically cut, using amilling device 689 adapted therefor, creating a straighter edge whichfacilitates the fixation of a medical device on the inside of the caputfemur.

FIG. 11 shows an artificial convex caput femur surface 112 adapted to beplaced in an artificial acetabulum surface according to any of theembodiments herein. After the artificial convex caput femur surface hasbeen placed in the artificial acetabulum surface it is locked using alocking member 116 comprising a surface 117 adapted to be in contactwith the artificial convex hip joint surface 112. The locking member 116further comprises fixating members 115 which are adapted to assist inthe fixation of the locking member 116 to the caput femur 5 or collumfemur 6, which in turns fixates the artificial convex hip joint surface112. The fixating members comprises a fixating portion 680 which travelson the outside of the surgically cut caput femur for radiallystabilizing and fixating the locking member to the surgically cut caputfemur. The artificial convex hip joint surface 112 is fixated to anattachment rod 113 comprising a thread 114.

FIG. 12 shows the artificial convex caput femur surface 112 as disclosedwith reference to FIG. 11 when mounted in an artificial acetabulumsurface 109 placed in a concave cavity in the femoral bone. Theartificial acetabulum surface is according to this embodiment is fixatedto the femoral bone using an elongated member 681, here being a threadedmember placed aligned with the collum and caput center axis.

FIG. 13 shows the artificial convex caput femur surface 112 as disclosedwith reference to FIG. 11 when mounted in an artificial acetabulumsurface 109 placed in a concave cavity in the femoral bone. Theartificial acetabulum surface is according to this embodiment is fixatedusing screws 121 entering the cortical bone of the surgically cut caputfemur.

FIG. 14 shows the injection of an adhesive 106 in the acetabulum 8 inthe pelvic bone 9 using an injecting member comprising an injectingnozzle 105, which is a preparation for the fixation of a medical deviceto the pelvic bone 9.

FIG. 15 shows the placing of a medical device in the reamed acetabulum 8surface of the pelvic bone 9. The medical device comprises a convex hipjoint surface 112 fixated to a fixation element 1301, which in turn isfixated to the acetabulum 8 using the injected fluid, which could beassisted or replaced by a mechanical fixation element such as screws.The medical device further comprises a pre-mounted locking member 116for locking the convex hip joint surface of the concave hip jointsurface placed in the caput 5 and collum femur 6 for hinderingdislocation of the hip joint when the hip joint is in its functionalposition.

FIG. 16 a shows the step of creating a hole in the pelvic bone 9 fromthe acetabulum side of the pelvic bone 9.

FIG. 16 b shows the medical device according to an embodiment in whichthe medical device comprises a fixation element 1301 adapted to fixatethe artificial convex caput femur 112 to the pelvic bone 9. The fixationelement 1301 comprises a fixation surface 1334 which is adapted to fitinto the acetabulum 8. The fixation surface 1334 could be adapted to befixated against the acetabulum 8 using an adhesive, such as bone cement,applied to the fixation surface 1334 and/or the acetabulum surface 8.The medical device further comprises an elongated element 1310, herebeing an integrated part of the fixation element 1301. The elongatedelement 1310 is inserted through the hole in the pelvic bone 9, suchthat said elongated member 1310 is partially placed on the abdominalside of the pelvic bone 9. After insertion of the elongated member 1310,the elongated member 1310 is structurally changed on the abdominal sideof the pelvic bone 9, such that said elongated member 1310 fixates thefixation element 1301 to the pelvic bone 9. According to the embodimentof FIG. 16 b the elongated member 1310 comprises an expandable portion1311, and the structural change comprises the expandable portion 1311changing from a first, non-expanded state, in which the elongatedelement 1310 is inserted into the hole in the pelvic bone 9substantially along a length axis of the elongated element 1310 into anexpanded state, in which the expandable portion 1311 is expanded in atleast one away from the length axis, such that said elongated element1310 is placed in an expanded state, which fixates the fixation element1301 to the pelvic bone 9. The expandable portion 1311 according to theembodiment shown in FIG. 16 b comprises a plurality of expandingelements in connection with an anvil member 1312. A threaded member 1313is placed centrally in the elongated element 1310 and is in one endconnected to an anvil member 1312 and in the other end connected to athreaded portion 1314 of the artificial caput femur 112. By theconnection with the threaded member 1313, the anvil member 1312 isadapted to press on the expanding elements following an action performedfrom the acetabulum side of the pelvic bone 9, such that said expandingelements expand in at least one direction substantially perpendicular tothe length axis of the elongated element 1311. The fixation elementshown in FIG. 16 b further comprises a flange 1315 adapted to extend outof the acetabulum 8 and be placed in contact with the pelvic bone 9.

FIG. 16 c shows the expandable portion 1311 when the anvil member 1312has pressed the expandable elements in two directions perpendicular tothe length axis of the elongated element 1310 for fixating the elongatedelement 1310 and the entire artificial caput femur 112 to the pelvicbone 9. The threaded part 1314, being a portion of the artificial caputfemur 112, has been partially inserted into the artificial caput femur112, and thus the anvil member 1312 is pulled towards the hole in thepelvic bone 9.

FIG. 16 d shows the elongated member 1311 in the wholly expanded statefixating the artificial caput femur 112 to the pelvic bone 9. In thisstate the threaded member 1313 is positioned further into the artificialcaput femur 112 which is rotated to tighten the expandable elongatedelement 1310. The locking member 116 is according to this embodimentpre-mounted onto the artificial caput femur 112 when the artificialcaput femur 112 is implanted, however, according to other embodiments itis equally conceivable that the locking member 116 is adapted to bemounted after the artificial caput femur 112 has been implanted in thehip joint.

FIG. 16 e shows the medical device according to an embodiment in whichthe implantable medical device comprises an elongated element 1320comprising a movable locking portion 1321 adapted to have a first andsecond state, wherein said movable locking portion 1321, in said firststate is adapted to be inserted into a hole in the pelvic bone 9, and insaid second state is adapted to hinder the elongated element 1320 frompassing through said hole in the pelvic bone 9 by said movable lockingportion 1321 contacting the surface of the pelvic bone 9 on theabdominal side. FIG. 8 f shows the elongated element 1320 in its firststate after having passed through the hole in the pelvic bone 9.

FIG. 16 f shows the movable locking portion 1321 changing from the firstto the second state at the same time as the artificial caput femur 112,comprising a threaded part 1314, interacts with a corresponding threadedmember 1323 being part of the elongated element 1320. The movablelocking portion 1321 is pivotally arranged at a pivot point 1322 andchanges from the first to the second state using the pivot point 1322.

FIG. 16 g shows the medical device according to the embodiment of FIGS.16 e and 16 f when the movable member 1321 is placed in the secondstate, in which the artificial caput femur 112 is fixated to the pelvicbone 9 by the movable member 1321 being in contact with the abdominalside of the pelvic bone 9. The artificial caput femur 112 has beentightened using the threaded part 1314 and corresponding threaded member1323, such that the entire medical device comprising the artificialcaput femur 112 is securely fixated to the pelvic bone 9. Similar to theembodiments shown with reference to FIGS. 16 b-16 d the fixation element1301 could be further fixated to the acetabulum 8 using an adhesive,such as bone cement, applied to the fixation surface and/or theacetabulum surface 8.

FIG. 16 h shows an embodiment in which the fixation element comprises afixation surface 1334 comprising two holes adapted to receive twomechanical fixation elements 1331. In the embodiment of FIG. 8 i themechanical fixation elements 1331 are expanding fixation elements 1331,such as the expanding fixation elements described with reference toFIGS. 16 b-16 d, however in other embodiments it is equally conceivablethat the mechanical fixation elements are elements adapted to fixate themedical device to the internal periphery of the holes, such as screws.Similar to the embodiments shown with reference to FIGS. 16 b-16 g thefixation element 1301 could be further fixated to the acetabulum usingan adhesive, such as bone cement, applied to the fixation surface and/orthe acetabulum surface. FIG. 16 h shows an embodiment in which themedical device has a pre-mounted locking member 116, however, in otherembodiments it is equally conceivable that the locking member 116 isadapted to be mounted after the artificial caput femur 112 has beenimplanted in the hip joint.

FIG. 16 i shows the artificial hip joint in section, when the medicaldevice described with reference to FIG. 16 h has been implanted.Furthermore an artificial acetabulum surface 1340 having a concavesurface towards the center of the hip joint has been implanted. Theartificial acetabulum surface 1340 has been fixated to the femoral bone7, and placed in movable contact with the artificial caput femur surface112, thus creating a functioning artificial hip joint. The lockingmember 116 has been fixated to the femoral bone 7, thus locking theartificial caput femur 112 in the artificial acetabulum surface 1340.The locking member 116 is according to the embodiment shown in FIG. 8 jfixated using screws 121, however the screws 121 could be assisted orreplaced by an adhesive, such as bone cement.

FIG. 17 a shows an assembled artificial hip joint with an artificialcaput femur surface 112 fixated to the pelvic bone 9 using two fixatingmembers adapted to expand inside of the cortical bone of the pelvic bone9. The fixating members comprises a screw 121 in connection with ananvil member 1312 affecting an expandable portion 1311 pressing theexpandable members in two directions perpendicular to the length axis ofthe fixation members for fixating the artificial caput femur 112 to thepelvic bone 9. The artificial acetabulum 1340 is fixated to the femoralbone 7 using an elongated member 1310 b placed in the cancellous boneand aligned with the caput and collum femur center axis. The elongatedmember comprises an expandable portion 1311 b which is pressed by ananvil member 1312 b connected to a threaded member 1313 b pressing theexpandable members 1311 b in two directions perpendicular to the lengthaxis of the elongated member 1310 b for fixating the artificialacetabulum surface to the femoral bone 7.

FIG. 17 b shows an embodiment similar to the embodiment shown in FIG. 17a with the difference that the artificial acetabulum surface is fixatedusing an elongated member 1310 c which penetrates the cancellous bone ofthe collum femur and the cortical bone of the femoral bone in the areaof the greater trochanter 1695. The elongated member comprises a movablelocking portion 1321 b, pivotally arranged at a pivot point 1322 b. Themovable locking portion 1321 b could change from a first to a secondstate around the pivot point 1322 b. When the movable locking portion1321 b is placed in the second state it locks the elongated member onthe outside of the femoral bone 7 in the area of the greater trochanter1695.

FIG. 17 c shows an embodiment similar to the embodiment shown in FIG. 17a with the difference that the artificial acetabulum surface is fixatedusing an elongated member 1310 d which penetrates the cancellous bone ofthe collum femur and enters the cortical bone of the femoral bone in thearea of the greater trochanter 1695 but never exits the bone but ratheris fixated inside of the bone 7.

FIG. 18 a shows an embodiment where the artificial acetabulum 1340 isfixated to the femoral bone 7 using fixating portions 680 being part ofthe locking member 116. The fixating portions 680 comprises portions680′ clasping the surgically cut femoral bone and thereby fixating theartificial acetabulum surface to the femoral bone.

FIG. 18 b shows an embodiment similar to the embodiment described withreference to FIG. 18 a with the difference that the locking member isfixated to the surgically cut caput femur using screws 121.

FIG. 19 shows the hip joint in section when the medical device isassembled and in its functional position in the hip joint. Theartificial caput femur surface 45 or convex hip joint surface 112 isfixated to the fixation part 1301, which in turn is fixated to theacetabulum 8, The locking member 116 locks the artificial convex caputfemur surface 45 in the artificial concave acetabulum surface in thecaput 5 and collum femur 6.

FIG. 20 shows a frontal view of a human patient when an incision forreaching an area of the hip joint through the pelvic bone in a surgicalmethod has been performed. According to one embodiment the incision 1 ismade in the abdominal wall of the human patient. The incision 1 passesthrough the abdominal wall, preferably rectus abdominis and peritoneum,in to the abdomen of the human patent. In a second embodiment theincision 2 is conducted through the rectus abdominis and in to thepelvic area, below peritoneum. According to a third embodiment theincision 3 is performed just between illium and the surrounding tissue,an incision 3 which could enable the pelvic bone to be dissected withvery little penetration of fascia and muscular tissue. According to afourth embodiment the incision 4 is made in the inguinal channel. In allof the four embodiments the tissue surrounding the pelvic bone 9 in thearea opposite to acetabulum is removed or penetrated which enables thesurgeon to reach the pelvic bone 9. It is obvious that the methodsdescribed may both be combined or altered reaching the same goal todissect the pelvic bone on the opposite side of the acetabulum.

FIG. 21 shows a frontal view of a human patient when small incisions forreaching an area of the hip joint through the pelvic bone in aarthroscopic method has been performed. According to a first embodimentthe incisions 14 is made in the abdominal wall of the human patient. Thesmall incisions enable the surgeon to insert arthroscopic trocars intothe abdomen of the human patient. According to the first embodiment theincisions 14 passes through the abdomen, preferably rectus abdominis andperitoneum, in to the abdomen of the human patent. According to a secondembodiment the small incisions 15 is conducted through the rectusabdominis and in to the pelvic area, below peritoneum. According to athird embodiment the small incisions 16 is performed just between illiumand the surrounding tissue, an incision 16 which could enable the pelvicbone to be dissected with very little penetration of fascia and musculartissue. According to a fourth embodiment the incision 17 is made in theinguinal channel. In all of the four embodiments the tissue surroundingthe pelvic bone 9 in the area opposite to acetabulum 8 is removed orpenetrated which enables the surgeon to reach the pelvic bone 9.

FIG. 22 shows the human patient in section when a medical device forcreating a hole 18 in the pelvic bone 9 is inserted through an incisionaccording to any of the embodiments described above. An elongated member21, which could comprise a part or section adapted to be bent transfersforce from an operating device (not shown) to the bone contacting organ22. The bone contacting organ 22 is placed in contact with the pelvicbone 9 and creates a hole through a drilling, sawing or milling processpowered by a rotating, vibrating or oscillating force distributed fromthe elongated member 21.

FIG. 23 shows the hip joint in section after the medical device forcreating a hole 18 in the pelvic bone 9 has created said hole 18.According to this embodiment the hole 18 is created through the removalof a bone plug 31, however it is equally conceivable that said medicaldevice comprises a bone contacting organ 22 adapted to create smallpieces of bone, in which case the medical device could further comprisea system for transport of said small pieces of bone.

FIG. 24 shows how the medical device adapted to create a hole isinserted into the hip joint and placed in contact with the caput femur5. According to this embodiment the medical device for creating a holein the pelvic bone 9 and surgically cutting the caput femur 5 is thesame medical device, however it is equally conceivable that there is asecond medical device particularly adapted to surgically cut the caputfemur 5.

FIG. 25 shows the hip joint in section when a second medical device 604surgically removes the most proximal portion of the caput femur 5. Thesecond medical device 604 comprises a drilling portion in which acutting member in a folded position 605 a is placed.

FIG. 26 shows the second medical device 604 when the drilling portion ispositioned inside of the femoral bone, and the cutting member is placedin a cutting position 605 b for cutting the proximal portion of thecaput femur 5.

FIG. 23 shows the caput femur 5 after the proximal part has been removedalong the section created by the medical device for creating a hole. Theremoving of the proximal part of the caput femur 5 create a surface of asection 102 in the cortical bone of the caput femur 5. A reamer 40adapted to create a concave surface 103 in the caput femur 5 is appliedto the elongated member 21 through a connecting section 101. Accordingto this embodiment the elongated member 21 is the same as the elongatedmember used for the medical device adapted to create a hole in thepelvic bone 9, however it is equally conceivable that the elongatedmember 21 is specifically designed to enable the reaming of the caputfemur 5. The reaming in the caput femur and part of the collum femur 6is mainly performed in the cancellous bone, however that does notexclude the possibility the some of the reaming needs to be performed inthe cortical bone of the caput femur 5 and/or the collum femur 6.

FIG. 17 shows the step of applying an adhesive 106 to the concavesurface created by the reamer 40. The adhesive 106 is applied by aninjecting member 104 comprising an injecting nozzle 105. The adhesive106 is preferably a biocompatible adhesive such as bone cement. Theinjecting member 104 is in this embodiment adapted for introductionthrough a hole 18 in the pelvic bone 9, through the injecting member 104being bent.

FIG. 18 shows the step of providing a medical device 109 comprising anartificial concave hip joint surface 110. The artificial concave hipjoint surface 110 is fixated to the concave surface 103 created in thecaput femur 5 and collum femur 6. The medical device 109 comprises afixation support 111 adapted to anchor said artificial concave hip jointsurface 110, to at least one of the caput femur 5 and the collum femur6. The medical device 109 is adapted to be introduced to the hip jointthrough a hole 18 in the pelvic bone 9 using a inserting member 107.According to this embodiment the inserting member is bent and therebyadapted to operate through a hole 18 in the pelvic bone 9. The insertingmember 107 comprises a connecting member 108 which is adapted to connectto the medical device 109. According to one embodiment the medicaldevice 109 comprises a self lubricating material such as PTFE, howeverit is also conceivable that said medical device comprises: titanium,stainless steel, Corian, PE, or other acrylic polymers, in which casethe medical device could be adapted to be lubricated after insertion inthe hip joint.

FIG. 27 shows a medical device comprising an artificial convex hip jointsurface 112. The artificial convex hip joint surface 112 is adapted tobe fixated to the pelvic bone 9, and is adapted to be inserted through ahole 18 in the pelvic bone 9. The medical device comprises a nut 120,comprising threads for securely fixating the medical device to thepelvic bone 9. The medical device further comprises a prosthetic part118 adapted to occupy the hole 18 created in the pelvic bone 9 after themedical device has been implanted in the patient. The prosthetic part118 comprises supporting members 119 adapted to be in contact with thepelvic bone 9 and assist in the carrying of the load placed on themedical device from the weight of the human patient in normal use.Normal use is defined as the same as a person would use a natural hipjoint. Further the medical device comprises a locking member 116comprising a surface 117 adapted to be in contact with the artificialconvex hip joint surface 112. The locking member 116 further comprisesfixating members 115 which are adapted to assist in the fixation of thelocking member 116 to the caput femur 5 or collum femur 6, which inturns fixates the artificial convex hip joint surface 112. Theartificial convex hip joint surface 112 is fixated to an attachment rod113 comprising a thread 114 that corresponds to the thread of the nut120 in connection with the prosthetic part 118.

FIG. 28 shows the hip joint in section when the artificial convex hipjoint surface is fixated in the medical device 109 comprising a concavehip joint surface 110. The convex hip joint surface 112 is secured inplace by the locking member 116 which is fixated to the caput femurusing screws 121. The surface of the locking member 117 and the concavehip joint surface 117 is placed in connection with the convex hip jointsurface and could be made of a friction reducing material such as PTFEor a self lubricating powder material. However it is also conceivablethat the connecting surfaces are lubricated using an implantablelubrication system adapted to lubricate the medical device after saidmedical device has been implanted in the human patient.

FIG. 29 shows the placing of a prosthetic part 118 adapted to occupy thehole 18 created in the pelvic bone 9. The prosthetic part 118 comprisessupporting members 119 adapted to be in contact with the pelvic bone 9and assist in the carrying of the load placed on the medical device fromthe weight of the human patient. According to the embodiment shown inFIG. 12 the supporting members 119 are located on the abdominal side ofthe pelvic bone 9, however it is equally conceivable the supportingmembers 119 are located on the acetabulum side of the pelvic bone 9, inwhich case they are preferably displaceable for allowing insertion ofthe prosthetic part 118 through the hole 18 in the pelvic bone 9.Furthermore FIG. 12 shows the fixation of a nut 120 to the attachmentrod 113. According to the embodiment shown in FIG. 12 the hole 18 in thepelvic bone 9 is adapted to be larger than the medical device allowingthe medical device to be inserted in its full functional size. Accordingto other embodiments the hole 18 is smaller in which case the medicaldevice could comprise of several parts adapted to be connected afterinsertion in the hip joint, or the medical device could be expandablefor insertion through a hole smaller than the full functional size ofthe medical device. The expandable medical device could be enabledthrough the elements of the medical device comprising elastic material.

FIG. 30 shows the hip joint in section when all the elements of themedical device has been fixated in the area of the hip joint or itssurroundings. The prosthetic part 113 adapted to occupy the hole 18 inthe pelvic bone 9 is here fixated with screws 121, however these screws121 could be assisted or replaced by an adhesive which could be appliedto the surface S between the prosthetic part and the pelvic bone 9.

FIG. 31 shows the hip joint in section when the method of supplying themedical device is conducted according to another embodiment. Theproximal part of the caput femur has been removed along the sectioncreated by the medical device for creating a hole. A reaming member 40adapted to create a concave surface 103 in the caput femur 5 is hereapplied to a elongated member 206 which is inserted through a hole 205going from the lateral side of the thigh, penetrating the cortical boneof the femoral bone 7 propagating along a length axis of the collumfemur in the cancellous bone and entering the area of the hip joint. Theelongated member 206 is operated using an operating device 207 whichcould be an electrically powered operating device, a hydraulicallypowered operating device or a pneumatically powered operating device.The reaming in the caput femur and part of the collum femur 6 is mainlyperformed in the cancellous bone, however that does not exclude thepossibility the some of the reaming needs to be performed in thecortical bone of the caput femur 5 or the collum femur 6.

FIG. 32 shows the step of applying an adhesive 106 to the concavesurface created by the reamer 40. The adhesive 106 is applied by aninjecting member 104 comprising an injecting nozzle 105. The adhesive106 is preferably a biocompatible adhesive such as bone cement. Theinjecting member 104 is in this embodiment adapted for introductionthrough a hole 18 in the pelvic bone 9, through the injecting member 104being bent.

FIG. 33 shows the step of providing a medical device 109 comprising anartificial concave hip joint surface 110. The medical device isaccording to this embodiment provided with a hole positioned in thelength axis of the collum femur 6. The medical device is through thehole adapted to be guided by the elongated member 206 or a guiding rodplaced in the hole 205 along a length axis of the collum femur 6.Inserting the medical device into the hip joint while the elongatedmember 206 or guiding rod runs through the hole of the medical devicefacilitates the positioning of the medical device and ensures thedifferent parts of the medical device is centered for functioning as aunit. In the embodiment shown in FIG. 33 the medical device 109 isinserted into the hip joint as a single unit, however it is equallyconceivable that the medical device 109 is inserted in parts (not shown)which are then connected to form the medical device after implantationin the patient. The artificial concave hip joint surface 110 is fixatedto the concave surface 103 created in the caput femur 5 and collum femur6. The medical device 109 comprises a fixation support 111 adapted toanchor said artificial concave hip joint surface 110, to at least one ofthe caput femur 5 and the collum femur 6. The medical device 109 isadapted to be introduced to the hip joint through a hole 18 in thepelvic bone 9 using a manipulation device 122 comprising a grippingmember 123. According to this embodiment the manipulation device 122 isbent and thereby adapted to operate through a hole 18 in the pelvic bone9. According to one embodiment the medical device 109 comprises a selflubricating material such as PTFE, however it is also conceivable thatsaid medical device comprises: titanium, stainless steel, Corian, PE, orother acrylic polymers, in which case the medical device could beadapted to be lubricated after insertion in the hip joint.

FIG. 34 shows the hip joint in section when the artificial convex hipjoint surface is fixated in the medical device 109 comprising a concavehip joint surface 110, the medical device is guided using the elongatedmember 206 or a guiding rod. The convex hip joint surface 112 is securedin place by the locking member 116 which is fixated to the caput femurusing screws 121, the convex hip joint surface is guided using theelongated member 206 or a guiding rod. The surface of the locking member117 and the concave hip joint surface 110 is placed in connection withthe convex hip joint surface and could be made of a friction reducingmaterial such as PTFE or a self lubricating powder material. However itis also conceivable that the connecting surfaces are lubricated using animplantable lubrication system adapted to lubricate the medical deviceafter said medical device has been implanted in the human patient. Theelongated member or guiding rod 206 can be adapted to act as a centeringrod for centering the at least one artificial hip joint surface insideof the hip joint. According to the embodiment shown the elongated member206 is inserted through the femoral bone, however according to otherembodiments, not shown, the elongated member is positioned inside of thehip joint from the acetabulum side.

FIG. 35 shows the placing of a prosthetic part 118 adapted to occupy thehole 18 created in the pelvic bone 9. The prosthetic part 118 comprisessupporting members 119 adapted to be in contact with the pelvic bone 9and assist in the carrying of the load placed on the medical device fromthe weight of the human patient. Furthermore FIG. 35 shows the fixationof a nut 120 to the attachment rod 113, which in turn is guided by theelongated member 206 or a guiding rod.

FIG. 36 shows the hip joint in section when all the elements of themedical device has been fixated in the area of the hip joint or itssurroundings. The prosthetic part 118 adapted to occupy the hole 18 inthe pelvic bone 9 is here fixated with screws 121, however these screws121 could be assisted or replaced by an adhesive which could be appliedto the surface S between the prosthetic part and the pelvic bone 9. Theelongated member 206 or guiding rod has been retracted through theincision in the thigh.

FIG. 37 shows an embodiment of a locking member 116, wherein the lockingmember 116 comprises a surface adapted to be in contact with theartificial convex hip joint surface 1353, the locking member 116 isadapted to, in a first state, lock the artificial caput femur 112 to theartificial acetabulum surface 1340, and in a second state, release saidartificial caput femur 112 from said artificial acetabulum 1340. Thelocking member 116 is adapted to change from the first to the secondstate when a predetermined amount of strain is placed on the lockingmember 116. The locking member 116 according to the embodiment shown inFIG. 37, comprises four elastic portions 1351, and the locking member116 is adapted to change from the first to the second state using theelasticity of the elastic portions 1351. The locking member 116 isadapted to be fixated to the femoral bone 7 using screws adapted to beplaced in holes 1352 adapted therefor.

FIG. 38 shows the hip joint in section when a two state locking member116 locks the artificial caput femur 112 in the artificial acetabulum1340. The two state locking member 116 is fixated to the femoral bone 7using screws 121, and is here shown in its first state in which thelocking member 116 locks the artificial caput femur 112 to theartificial acetabulum 1340.

FIG. 39 shows the hip joint in section according to the embodiment ofFIG. 38, but when the two state locking member 116 is in its secondstate, in which the locking ring 116 releases the artificial caput femur112 from the artificial acetabulum surface 1340. The construction withthe releasing locking ring 116 reduces the risk of strain placed on theartificial joint injuring the fixation points, i.e. the contact withbone; it further enables the artificial joint to be non-invasivelyrelocated in case of luxation.

According to the above mentioned embodiments the medical device isadapted to be inserted through a hole in the pelvic bone, however it isequally conceivable that the medical device according to any of theembodiment above is adapted to be inserted through a hole in the hipjoint capsule or the femoral bone of the human patient.

Please note that any embodiment or part of embodiment as well as anymethod or part of method could be combined in any way. All examplesherein should be seen as part of the general description and thereforepossible to combine in any way in general terms.

The invention claimed is:
 1. A medical device for implantation in a hipjoint of a human patient, the natural hip joint having a ball shapedcaput femur as the proximal part of the femoral bone with a convex hipjoint surface towards a central location of the hip joint between thecaput femur and the acetabulum and a bowl shaped acetabulum as part ofthe pelvic bone with a concave hip joint surface, the medical devicecomprising; an artificial caput femur, comprising a convex surface,wherein said artificial convex caput femur is adapted to, whenimplanted, be immovably fixated to the pelvic bone of the human patient,and be in movable connection with an artificial acetabulum surfacefixated to the femoral bone of the patient, thereby forming a ball andsocket joint, wherein the medical device further comprises a fixationelement comprising a convex fixation surface adapted to be in contactwith the surface of the acetabulum and adapted to fixate the artificialconvex caput femur to at least the acetabulum of the pelvic bone,wherein the medical device further comprises an artificial acetabulumcomprising a concave surface towards the centre of rotation of the hipjoint, adapted to when implanted, be fixated to the femoral bone of thehuman patient, and be in movable connection with the artificial caputfemur surface fixated to the pelvic bone of the patient, and wherein themedical device further comprises a second fixation element comprising asecond fixation surface adapted to be in contact with the caput femur orcollum femur, wherein said second fixation element is adapted to fixatethe artificial concave acetabulum to the femoral bone.
 2. The medicaldevice according to claim 1, wherein said fixation surface comprises atleast one hole adapted to receive a mechanical fixation element.
 3. Themedical device according to claim 1, wherein said fixation surface isadapted to fixate said medical device to the pelvic bone using anadhesive placed between said fixation surface and said surface of theacetabulum, when said device is implanted in the hip joint.
 4. Themedical device according to claim 1, wherein said fixation elementcomprises an elongated member, and wherein said elongated member isadapted to: a. be inserted through a hole in the pelvic bone, such thatsaid elongated member is adapted to be partially placed at least one of:i. inside of the pelvic bone, and ii. on the abdominal side of thepelvic bone, and b. be structurally changed inside of the pelvic bone,such that said elongated member is adapted to fixate the fixationelement to the pelvic bone, and adapted to be contacting the pelvic boneon the inside thereof, when implanted.
 5. The medical device accordingto claim 4, wherein said elongated member comprises an expandableportion, wherein said expandable portion is adapted to: a. in a first,non-expanded state, be inserted through the hole in the pelvic bone,substantially along a length axis of said elongated member, b. expand atleast in one direction other than the direction of the length axis, suchthat said elongated member is placed in an expanded state, which fixatesthe fixation element to the pelvic bone, on the inside thereof.
 6. Themedical device according to claim 4, wherein said elongated membercomprises an expandable portion, wherein said expandable portion isadapted to: a. in a first, non-expanded state, be inserted through thehole in the pelvic bone, substantially along a length axis of theelongated member, b. expand at least in one direction away from saidlength axis, such that said elongated member is placed in an expandedstate, which fixates the fixation element to the pelvic bone.
 7. Themedical device according to claim 6, wherein said expandable portioncomprises two or more expanding elements in connection with an anvilmember, wherein said anvil member is adapted to press, on the expandingelements, such that said two or more expanding elements expands in atleast one direction substantially perpendicular to the length axis ofthe elongated member.
 8. The medical device according to claim 6,wherein said expandable portion of said elongated member is adapted to:expand in at least one direction away from said length axis in responseto the expandable portion being exposed to a rotational movement actingon the expandable portion, when said device is implanted.
 9. The medicaldevice according to claim 6, wherein said expandable portion is adaptedto expand in at least one direction substantially perpendicular to thelength axis of said elongated member.
 10. The medical device accordingto claim 7, wherein said anvil member is in connection with a threadedmember extending substantially along the length axis of the elongatedmember, and wherein said medical device further comprises acorresponding threaded part, and wherein said threaded member is adaptedto be pulled in the direction of the acetabulum side of the pelvic bone,when said corresponding threaded part is rotated, such that theconnection with the anvil member presses said two or more expandingelements.
 11. The medical device according to claim 4, wherein saidelongated member comprises a movable locking portion adapted to have afirst and second state, wherein said movable locking portion, in saidfirst state is adapted to be inserted into a hole in the pelvic bone,and in said second state is adapted to hinder the elongated member frompassing through said hole in the pelvic bone by said movable lockingportion contacting the surface of the pelvic bone on the abdominal sidethereof.
 12. The medical device according to claim 11, wherein saidmovable locking portion is pivotally arranged to said elongated member.13. The medical device according to claim 1, wherein the artificialcaput femur comprises a threaded part adapted to engage a correspondingthreaded member, and wherein said artificial caput femur is adapted tobe further fixated to the pelvic bone by a rotating movement of theartificial caput femur in relation to said threaded part.
 14. Themedical device according to claim 2, wherein said fixation elementfurther comprises an elongated member adapted to be placed in said hole,wherein said elongated member is further adapted to: a. be insertedthrough a hole in the pelvic bone, the elongated member is thus adaptedto be partially placed on the abdominal side of the pelvic bone, and b.be structurally changed on the abdominal side of the pelvic bone, andthe elongated member is thus adapted to fixate the fixation element tothe pelvic bone.
 15. The medical device according to claim 2, whereinsaid fixation element further comprises two or more elongated membersadapted to be placed in two or more holes in said fixation surface,wherein said elongated elements are further adapted to; a. be insertedthrough holes in the pelvic bone, such that said elongated elements arepartially placed on the abdominal side of the pelvic bone, and b. bestructurally changed on the abdominal side of the pelvic bone, such thatsaid elongated elements fixates the fixation element to the pelvic bone.16. The medical device according to claim 1, further comprising anelongated member comprising an expandable portion adapted to: in afirst, non-expanded state, be inserted through a hole in the femoralbone, substantially along a length axis of the elongated member, andexpand at least in one direction away from said length axis, such thatsaid elongated member is placed in an expanded state, which fixates thefixation element to the femoral bone, from the inside thereof.
 17. Themedical device according to claim 1, wherein said artificial acetabulumsurface comprises at least one beyond part adapted to pass beyond theequator of the artificial caput femur, clasping said artificial caputfemur for fixating said artificial caput femur in said artificialacetabulum surface.